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    SubjectRe: [PATCH] Documentation: Fix NUL termination of strncpy
    On Tue, 17 Nov 2009 12:25:03 GMT, Pádraig Brady said:

    > You need to explicitly NUL terminate strncpy():

    Umm. Actually, no. It's *nice* if you explicitly do it. However, it's
    not strictly *required*. Consider this code:

    struct a {
    int b, c;
    char d[20];

    bzero(a,sizeof(a)); /* voila! a->d[19] is now a \0 */

    Perfectly valid and we do it all the time. Your referenced web page comments
    that using memset() or bzero() is inefficient - I wonder if they actually
    *tested* the difference between using one memset() or bzero() on a large
    structure compared to lots and lots of explicit initialization statements
    (i-cache issues probably most important there). The downside is that there's a
    greater chance of some programmer refactoring code and bollixing it up. (The
    astute reader will remember a short thread about this not too long ago.. :)

    And if you're truly careful and always use the strn- variants of the string
    functions, it's actually possible to *not* null-terminate the strings. But
    it results in very brittle code and makes Baby Andrew cry, mostly because when
    somebody adds a printf() to debug the brittle code, it suddenly becomes even
    more brittle... :)
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      Last update: 2009-11-17 17:43    [W:0.038 / U:15.108 seconds]
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